Purpose: To model and predict the dynamics of conductive nonmagnetic objects within the MRI room under the influence of Lenz effect. Methods: The dynamics are described by an ordinary differential equation and the Lenz effect approximated by recognizing that the skin effect is negligible. This separated Lenz effect dependency on the object position and velocity, leading to a simple numerical procedure for objects of any shape. Results: The model and numerical procedure were validated with experimental data recording the rotation of an aluminum plate falling inside a 1.5 T MRI scanner. The model was also applied for studying the translation of an aluminum plate pushed with constant force towards the MRI bore through the fringe field. Conclusion: The collected results showed that it is possible to obtain accurate predictions of motion in the presence of Lenz effect by neglecting the skin effect while determining the electric currents induced in the metallic object during each infinitesimal motion step.

翻译：目的：建立并预测磁共振成像室内导电非磁性物体在楞次效应影响下的动力学行为。方法：通过常微分方程描述物体动力学，并基于趋肤效应可忽略的假设对楞次效应进行近似建模。该方法将楞次效应分解为对物体位置和速度的依赖关系，从而建立了适用于任意形状物体的简化数值计算流程。结果：通过记录铝板在1.5 T磁共振扫描仪内坠落旋转过程的实验数据，验证了模型与数值方法的有效性。该模型还应用于研究铝板在恒定推力作用下穿过边缘磁场向磁体孔道平移的运动过程。结论：研究结果表明，在金属物体每个无限小运动步长中确定感应电流时，通过忽略趋肤效应可获得楞次效应作用下运动的精确预测。